gpu: ion: Stop trying to allocate from an order on first failure

With this patch the system heap will only try to allocate from each
order as long as allocations succeed.  If it failes to obtain a higher
order allocation, it doesn't retry that order.

Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
[jstultz: modified patch to apply to staging directory]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/android/ion/ion_system_heap.c b/drivers/staging/android/ion/ion_system_heap.c
index ef8afc7e4e72a8708217dcc4e35e1935771dbecc..30a225a92c403b6ab521c4850946cf2c6b8c454b 100644 (file)
--- a/drivers/staging/android/ion/ion_system_heap.c
+++ b/drivers/staging/android/ion/ion_system_heap.c
@@ -32,7 +32,8 @@ struct page_info {
 };
 
 static struct page_info *alloc_largest_available(unsigned long size,
-                                                bool split_pages)
+                                                bool split_pages,
+                                                unsigned int max_order)
 {
        static unsigned int orders[] = {8, 4, 0};
        struct page *page;
@@ -42,6 +43,8 @@ static struct page_info *alloc_largest_available(unsigned long size,
        for (i = 0; i < ARRAY_SIZE(orders); i++) {
                if (size < (1 << orders[i]) * PAGE_SIZE)
                        continue;
+               if (max_order < orders[i])
+                       continue;
                page = alloc_pages(GFP_HIGHUSER | __GFP_ZERO |
                                   __GFP_NOWARN | __GFP_NORETRY, orders[i]);
                if (!page)
@@ -71,13 +74,17 @@ static int ion_system_heap_allocate(struct ion_heap *heap,
        bool split_pages = ion_buffer_fault_user_mappings(buffer);
 
 
+       unsigned int max_order = orders[0];
+
        INIT_LIST_HEAD(&pages);
        while (size_remaining > 0) {
-               info = alloc_largest_available(size_remaining, split_pages);
+               info = alloc_largest_available(size_remaining, split_pages,
+                                              max_order);
                if (!info)
                        goto err;
                list_add_tail(&info->list, &pages);
                size_remaining -= (1 << info->order) * PAGE_SIZE;
+               max_order = info->order;
                i++;
        }